Prime Minister Habib Essid sacked the heads of police for Tunis and the area around the National Bardo Museum, site of the assault claimed by the Islamic State group, after finding “several deficiencies” in security. The dismissals came as the museum prepared to reopen in what organisers said was “a message” to the gunmen who killed 20 tourists and a police officer last Wednesday. “It’s a challenge but also a message... we want to show that they haven’t achieved their goal,” museum curator Moncef Ben Moussa said.

Tunisia fears that last week’s carnage - the deadliest assault on foreigners in the North African country since 2002 - will hit its vital tourism sector.

In a move aimed at restoring confidence, Essid “decided to fire a number of officials including the Tunis police chief and the police chief for the Bardo,” his communications director Mofdi Mssedi told AFP.

But in a reminder of the fragile security situation in the country credited as the birthplace of the Arab Spring uprisings, a soldier was killed and two wounded late Sunday near the border with Algeria.

“Definitely there were three,” he told France media iTele television and Europe 1 radio. “Two were killed, but there is one who is now on the run,” Essebsi said. “In any case, he will not get very far.”

Officials had previously named two gunmen shot dead by security forces after the attack and said they had received training at militant camps in neighbouring Libya.

Authorities say as many as 3,000 Tunisians have gone to Iraq, Syria and Libya to join militant ranks, raising fears of returning battle-hardened militants plotting attacks.

Writing in Monday’s edition of the French Le Figaro newspaper, Essid admitted there were security “failures” around the museum and vowed to “take the necessary steps... to defend” Tunisia.

On Saturday, authorities released CCTV footage showing two black-clad gunmen with automatic weapons walking unimpeded though a large lobby in the Bardo, just after noon.

The grainy footage then shows the gunmen passing an unidentified male. They point an automatic weapon at him briefly before letting him leave as they make their way up a staircase.

Secretary of State for Security Rafik Chelly said Sunday that the video showed “one of the two Vespa drivers that brought the killers”.

Activists called for demonstrations outside the museum and a protest arranged by the organisers of the Global Social Forum, a mass anti-globalisation event held in Tunis this week, is expected to draw thousands on Tuesday.